海安凹陷南部地区泰州组一段储层沉积相研究

Sedimentary Facies of K_2t_1 Reservoir in the South of Hai'an Depression

为了对海安凹陷南部地区泰州组一段(K2t1)储层的沉积相有一个明确的认识,以岩心相分析为基础,综合海安凹陷K2t1砂岩储层的储层岩性、沉积构造及粒度等方面的特征,对沉积相平面展布规律进行了研究和分析,确定了研究区目的层段以三角洲沉积体系为主,主要为三角洲前缘亚相;微相有水下分流河道、河口坝、分流间湾、远砂坝、席状砂和水下天然堤,其中水下分流河道、河口坝和远砂坝是勘探的有利相带,绘制了沉积相平面图,为储层预测奠定了地质基础。

The characteristics of lithology,sedimentary structure and grain sizes of K2t1 sandstone reservoirs of Hai'an Depression were described in order to clarify the sedimentary facies of K2t1 Reservoir in the south of Hai'an Depression on the basis of the core facies analysis.The rules of plane distribution of sedimentary facies were analyzed.It was determined that the target zones of the studied area were mainly of delta sedimentary systems and the delta front subfacies.The microfacies include the underwater distributary channel,channel mouth bar,bay beside distributary channel,distal bar,sand sheet and underwater natural levee,in which the underwater distributary channel,channel mouth bar and distal bar are the advantageous facies belts.The planar graphs of sedimentary facies are drawn,it provides a foundation for reservoir prediction.